It seems to me to argue not that the Bohmian stance is that the wavefunction isn’t a thing, but that one good Bohmian stance is that the wavefunction isn’t a thing. Of course that might suffice as a rebuttal to the common claim that Bohmian mechanics is basically a less honest version of MWI plus some extra unnecessary bits.
… Though the paper’s approach doesn’t seem perfectly satisfactory to me—the proposal is that the universal wavefunction should be considered a law of nature, which seems to me about as reasonable as considering every fact about the universe a “law of nature” and doing away with contingency altogether. I confess that I don’t have much in the way of actual arguments against doing this, though. It just seems to violate a general pattern I think I see, that it works best to put random-contingent-looking stuff in (so to speak) the data rather than the code.
(… And: even if we deny that the wavefunction is a thing, the usual argument still seems to me to have considerable force: Bohmian mechanics includes all the same stuff as Everettian, even if it reclassifies some bits as laws rather than things, plus extra stuff—all those ontologically basic particles—that seems to serve no purpose beyond making the theory feel a bit more natural to some physicists.)
It might turn out (I suspect only with a complete theory of quantum gravity in hand) that actually there’s a really briefly specifiable universal wavefunction that naturally gets everything we see as one of its branches. In that case, my objection to treating the wavefunction as a law of nature rather than a part of nature would probably go away. I’m not sure it would really do much to make Bohmian QM look better than Everettian, though.
(Disclaimer: I’m not really a physicist or a philosopher of science, and my intuitions on this stuff aren’t worth very much.)
Interesting paper—thanks!
It seems to me to argue not that the Bohmian stance is that the wavefunction isn’t a thing, but that one good Bohmian stance is that the wavefunction isn’t a thing. Of course that might suffice as a rebuttal to the common claim that Bohmian mechanics is basically a less honest version of MWI plus some extra unnecessary bits.
… Though the paper’s approach doesn’t seem perfectly satisfactory to me—the proposal is that the universal wavefunction should be considered a law of nature, which seems to me about as reasonable as considering every fact about the universe a “law of nature” and doing away with contingency altogether. I confess that I don’t have much in the way of actual arguments against doing this, though. It just seems to violate a general pattern I think I see, that it works best to put random-contingent-looking stuff in (so to speak) the data rather than the code.
(… And: even if we deny that the wavefunction is a thing, the usual argument still seems to me to have considerable force: Bohmian mechanics includes all the same stuff as Everettian, even if it reclassifies some bits as laws rather than things, plus extra stuff—all those ontologically basic particles—that seems to serve no purpose beyond making the theory feel a bit more natural to some physicists.)
It might turn out (I suspect only with a complete theory of quantum gravity in hand) that actually there’s a really briefly specifiable universal wavefunction that naturally gets everything we see as one of its branches. In that case, my objection to treating the wavefunction as a law of nature rather than a part of nature would probably go away. I’m not sure it would really do much to make Bohmian QM look better than Everettian, though.
(Disclaimer: I’m not really a physicist or a philosopher of science, and my intuitions on this stuff aren’t worth very much.)